﻿#region License

// Another free, open solution by folks who get it.
// Copyright © 2011 Business in Unison, Inc.
// 
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

#endregion

using System.Text.RegularExpressions;

namespace Patterns.Text
{
	/// <summary>
	/// 	Defines a regular expression that is always compiled, and that can be
	/// 	created via implicit string conversion.
	/// </summary>
	public class CompiledRegex : Regex
	{
		/// <summary>
		/// 	Initializes a new instance of the <see cref = "CompiledRegex" /> class.
		/// </summary>
		/// <param name = "pattern">The pattern.</param>
		public CompiledRegex(string pattern) : this(pattern, RegexOptions.None) {}

		/// <summary>
		/// 	Initializes a new instance of the <see cref = "CompiledRegex" /> class.
		/// </summary>
		/// <param name = "pattern">The pattern.</param>
		/// <param name = "options">The options.</param>
		public CompiledRegex(string pattern, RegexOptions options) : base(pattern, GetOptions(options)) {}

		/// <summary>
		/// 	Performs an implicit conversion from <see cref = "System.String" /> to 
		/// 	<see cref = "CompiledRegex" />.
		/// </summary>
		/// <param name = "pattern">The pattern.</param>
		/// <returns>
		/// 	The result of the conversion.
		/// </returns>
		public static implicit operator CompiledRegex(string pattern)
		{
			return new CompiledRegex(pattern);
		}

		private static RegexOptions GetOptions(RegexOptions originalOptions)
		{
			if ((originalOptions & RegexOptions.Compiled) != RegexOptions.Compiled) originalOptions |= RegexOptions.Compiled;
			return originalOptions;
		}
	}
}